The MX Tech WP Shock Huck Valve is a bottoming control valve comprised of a speed sensitive piston that sits above the shock main piston and the red engagement valve that assembles into the top of the inner shock body. Near the bottoming stroke of the shock the MXT Shock Huck Piston enters the red MXT Shock Huck Engagement Valve generating much needed additional damping to resist hard bottom outs. Since the MXT Shock Huck only functions during the last part of the travel tuners are able to build a very plush shock that would normally bottom under regular use. Its the best of both worlds. Great bottoming control and a plush ride up top.